Four component amide copolymer

Abstract

Polymeric material comprising at least four polymeric constituents which comprise mer units of the following types: I acrylamide or derivatives thereof II acrylonitrile or derivatives thereof III acrylic acid and esters, or derivatives thereof IV alkylol, sulphonyl or phosphonyl derivatives of I. The polymeric materials are useful as components of water bearing systems which are in the form of gels or suspensions.

We claim: 
     
       1. A water-soluble copolymer consisting essentially of: (a) from 65.0 to 98.5 mole percent of repeating units of formula I ##STR10## (b) from 0.5 to 10.0 mole percent of repeating units of formula II ##STR11## (c) from 0.5 to 4.0 mole percent of repeating units of formula III ##STR12## (d) from 0.5 to 25.0 mole percent of repeating units of formula IV ##STR13## wherein in the formulae R 1 , R 2 , R 3 , R 4  and D are independently chosen from hydrogen, C 1  to C 6  alkyl and C 1  to C 6  hydroxyalkyl; A is chosen from hydrogen and C 1  to C 6  alkyl; and E is C 1  to C 6  hydroxyalkyl.   
     
     
       2. A copolymer according to claim 1 wherein said repeating units of formula III comprise two sub-types of formulae IIIA ##STR14## and IIIB ##STR15## wherein R 3A  and R 3B  may be the same or different and D 1  and D 2  are different. 
     
     
       3. A copolymer according to claim 1 wherein said R 1 , R 3  and R 4  radicals are the same. 
     
     
       4. A copolymer according to claim 1 wherein the repeating units of formula I type are the mer units of poly(acrylamide). 
     
     
       5. A copolymer according to claim 1 wherein the repeating units of formula II type are the repeating units of poly(acrylonitrile). 
     
     
       6. A copolymer according to claim 1 wherein the repeating units of formula III type are of a type selected from the repeating units of the group of polymers consisting of poly(acrylic acid) and poly(hydroxyethylmethacrylate). 
     
     
       7. A copolymer according to claim 2 wherein the repeating units of formula IIIA type are the mer units of poly(acrylic acid) and the repeating units of the formula IIIB type are the repeating units of poly(hydroxyethylmethacrylate). 
     
     
       8. A copolymer according to claim 1 which comprises from 80.0 to 95.0 mole percent of a repeating unit of formula I. 
     
     
       9. A copolymer according to claim 1 which comprises from 1.0 to 5.0 mole percent of a repeating unit of formula II. 
     
     
       10. A copolymer according to claim 1 which comprises from 1.0 to 3.5 mole percent of a repeating unit of formula III. 
     
     
       11. A copolymer according to claim 1 which comprises from 1.0 to 12.0 mole percent of a repeating unit of formula IV. 
     
     
       12. A water soluble copolymer comprising (a) from 80.0 to 95.0 mole percent of repeating units of formula ##STR16## (b) from 1.0 to 5.0 mole percent of repeating units of formula ##STR17## (c) from 0.5 to 3.5 mole percent of repeating units of formulae ##STR18## (d) from 1.0 to 12.0 mole percent of repeating units of formula ##STR19##   
     
     
       13. A copolymer according to claim 1 selected from the group consisting of random copolymers, block copolymers and graft copolymers. 
     
     
       14. A process for the preparation of a copolymer as defined according to claim 1 which process comprises either: (a) copolymerizing an appropriate mixture of monomers; or   (b) copolymerizing a mixture of monomers to give a precursor copolymer comprising at least the repeating units of formula I and formula II, as defined according to claim 34, and modifying said precursor copolymer by graft copolymerization or chemical treatment to introduce repeating units of formula III and formula IV, as defined according to claim 1.   
     
     
       15. A process according to claim 14 wherein said chemical treatment is effected by a method selected from the group of methods consisting of hydrolysis, esterification, hydroxy-alkylation, amination. 
     
     
       16. A process according to claim 14 wherein said graft polymerisation is effected by using a chemical free radical initiator or radiation initiation.